Freeze: The Antarctic Treaty Turns 50

On the first of December 1959, 12 nations signed a pact freezing territorial claims and banning military activity in Antarctica. It isn't human-free (29 nations have research stations there, and 11 people have been born on the continent), but it remains remarkably untouched. Here's a tour.

5. Tourism is one of Antarctica's two main industries. Antarctica had 37,858 tourists last year. Most visitors arrived by sea — a typical 10-day cruise to the region runs from $5,000 to $10,000 per person — and nearly all landed on the Antarctic Peninsula. No ship carrying more than 500 passengers may land in Antarctica.

6. Fishing is Antarctica's other principal industry. The annual quota for the legal Antarctic krill fishery, centered in the Southern Ocean, is 4 million tons. The tiny crustacean is used to make feed for fish farms and omega-3 oils for health supplements.

7. Illegal fishing takes thousands of tons of seafood from Antarctic waters each year. One prime target in the South Pacific: the toothfish, also known as Chilean sea bass.

8. Antarctica is home to nearly 40 million penguins. The biggest population of the Emperor, the tallest species and star of March of the Penguins, is in the Ross Sea Sector, where more than 80,000 pairs breed.

9. The West Antarctic Ice Sheet Divide is the best place on earth for scientists to harvest ice cores — cross sections of ancient ice with trapped air bubbles that provide data about the earth's atmospheric history. The longest Antarctic ice core on record: 4,961 feet.

10. The Bentley Subglacial Trench has the lowest elevation of any piece of land on earth, at 2,450 meters below sea level.

11. It's estimated that fewer than 10,000 people have ever visited the South Pole.